2. ASSISTED VENTILATION By: Dr.Saif Assistant Professor Of Paediatrics Allied Hospital Faisalabad.

3. Definition “Movement of gas into and out of lungs by an external source connected to the patient”

4. History  Hipocrates (400 B.C) work ignored for next 1000 years.  Paracealsus (1493-1541) Bellow and oral tube.

5.  Vide Chaussier and his successors (1879). Aerophore pulmonare.

6.  Fell-O’Dwyer apparatus (1887)

7.  Alexander Graham Bell’s Negative Pressure Ventilator(1889)

8. Five Ws of assisted ventilation  WHO  WHEN  WHAT  WHERE  WHY

9. Types of ventilators  Negative pressure ventilators e.g, Airshield “Isolette respirator” Advantages: o Less oxygen toxicity o Less pulmonary infection o Less chances of atelectasis o Less pulmonary air leaks o Less airway trauma Disadvantages: o Patient inaccessible for routine investigations o Hypothermia o Neck abrasions o o Not effect for V.L.B.W

10. Negative Pressure Ventilator

11.  Positive pressure ventilators: Classification (by cycling mode); Time cycled: o Electrical e.g; Sechrist, Bourns BP 200, o Healthdyne 100,Bear Cub, o Pneumatic e.g; Baby bird Volume cycled: o e.g.; Siemens,Bourns LS-104-150, Bonnett,Emerson Pressure cycled Flow cycled Mixed cycling

12. Positive Pressure Ventilator

13.  High Frequency Ventilators: Delivers small gas volumes at high frequency.

14. Classification of positern press ventilatoron (by cyclic mod)  Volume cycled  Pressure cycled  Time cycled  Mined cycled

15. Satisfactory ventilator All models of ventilation, should be  Simple,  Reliable,  Small,  Inexpensive,  Wide range of respiratory rate upto 150,  FiO 2 21 to 100%,  Alarm system etc.

17. “IT IS NOT THE GUN BUT MAN BEHIND THE GUN” 1965 Lancet editorial: The tedious argument about the virtues of respirators not invented over those readily available can be ended now that it is abundantly clear that the success of such apparatus depends on the skill with which it is used.

18. Mode control mode  Control mode: Ventilator will take total control  Assist mode Ventilator initiate inspiration when pt generates sub base line pressure trigger level  Asst/cont. Mode: Vent is set at certain level and its responds to all breathing efforts by the patient reaching trigger level. If patients rate falls below preset rate it will automatically enter control mode.  IMV: Control mode + unhandled spontaneous ventilation by the pt.  SIMV:  CPAP: Maintain increased transpulomanary pressure during expiratory phase of respiration.

19. Ventilation settings  Flow Rate: 7L/min (4-10L/min) High flow rate when inspiratory time shortened A minimum flow of at least two times the infant calculated minute ventilation (tidal Volume * RR) e.g. 10 Kg 70 50/3.50L/min  1:E Ration  1:1: to 1:2  2. Oxygen Con (FiO 2 : 50-70%  3. Peak Inspiratory pressure (PIP) 20-25cmH 2 O range (5 to 10 cm H 2 O)  4. Respi ratory rate frequency (f): varies 2- 150/min range  5. Positive end expiratory pressure (PEEP): 4-7 cm/H 2 O  6. Wave form range: taper(sin) to square  Mean air way pressure 5.0 to 80 cm H 2 O the mean of installations readings of press with in the air way  Bar graph patient pressure display  Breath status indicator  D/C power indicator  Battery power indicator  Visual Alarm indicator  Message display  Alarm setting indicator  Alarm Delay setting /display  Means R/R  Trigger/Sensor sensitivity setting display  Set respiratory display.